Switchable lock for knitting machines

ABSTRACT

Cams in knitting machines are movable between operative and inoperative positions and are biased as by springs toward one position and are held in the other position against the spring bias by a detent engaging latching bolt controlled by an electromagnet and movable along a path perpendicular to the direction of cam movement.

United States Patent [191 Schieber et al.

[111 3,766,754 Oct. 23, 1973 SWITCI-IABLE LOCK FOR KNITTING MACHINES [75] Inventors: Hans Schieber; Erich Krause, both of Bopfingen, Germany [73] Assignee: Universal Maschineniabrik Dr.

Rudolf Schieber G.m.b.H., Westhausen, Germany 22 Filed: on. 22, 1971 21 Appl. No.: 191,638

[30] Foreign Application Priority Data Mar. 11, 1971 Germany P 21 11 789.5

' 52 US. Cl 66/78 R [51] Int. CL... D04b 7/00,-D04b 15/36, D04b 35/00 [58] Field of Search 66/78, 60, 64, 74

[56] References Cited UNITED STATES PATENTS 1,571,765 2/1926 Fels 66/75 Levine et al. 66/154 A 3,232,079 2/1966 3,229,482 1/1966 Farmer 3,340,708 9/1967 Krause 66/78 FOREIGN PATENTS OR APPLICATIONS 1,435,132 10/1968 Germany "6 6/75 1,435,161 10/1968 Germany ..66/78 Primary Examiner-Ronald Feldbaum AttorneyJoseph M. Fitzpatrick et a1.

[57] ABSTRACT Cams in knitting machines are movable between operative and inoperative positions and are biased as by springs toward one position and are held in the other position against the spring bias by a detent engaging latching bolt controlled by an electromagnet and movable along a path perpendicular to the direction of cam movement.

9 Claims, 6 Drawing Figures SWITCHABLE LOCK FOR KNITTING MACHINES This invention relates to switchable cam locks for knitting machines. The invention is particularly suited to flat knitting machines wherein the selection and fixing of the positions of various cam parts is obtained by mechanical adjustment of individual cam parts and the holding of these parts by electromagnets in their adjusted position.

Cam switching operations in knitting machines, which heretofore have been carried out mechanically, are now being effected increasingly through the use of electromagnets. In the case of one type of such switching processes, the cam parts are connected directly to the electromagnets which, when energized, attract and bring the lock or cam into action. The previously known switching devices of this type suffer from disadvantage that they' require very large electromagnets in order to move and hold the cam parts. As a result, the size and weight of the switching device is quite large; and the carriage of the knitting machine, which is equipped with such electromagnets, must, therefore, be capable of moving a very large amount of weight. Furthermore, it becomes difficult to arrange these large electromagnets in the small space in which the lock or cam parts lie.

It has been proposed to bring the cam parts into operation by means of a mechanical switching device which provides a spring force at each end of a carriage stroke through the use of levers controlled by cams. In such arrangements, the electromagnets would attract, in accordance with a predetermined program, and hold the lock or cam parts in the desired position after removal from the mechanical switching device. With this construction, the electromagnet need not lift the lock parts, but instead it need only to hold them in lifted position, that is, it acts only in its holding position. Since the holding force of an electromagnet is substantially greater than its force of attraction, theelectromagnets could be made correspondingly smaller. With this apparatus also the spring force ;of the switched lock or cam part still acts in the direction of stroke of the electromagnet, although only in its holding position. The above-described difficulties associated with the construction and operation of the cam are somewhat lessened; nevertheless, they are still present to a consider able extent. I

It is an object of the present invention to provide a switchable cam arrangement for knitting machines in which the cam parts can be mechanically displaced and held in their displaced position by devices which can be controlled by the smallest possible electromagnets.

This object is achievedin accordance with the invention in the manner that mechanical switching devices are provided for the optional displacement of the individual cam parts and that locking devices switched by the electromagnets are so arranged that the forces which effect the switching and holding of the cam parts do not have any componentsin the direction of stroke of the electromagnets.

As illustratively embodied, the cam arrangement of the present invention utilizes a'detent engaging bolt which is movable into and out of a detent groove in a direction perpendicular to the direction of movement of the cam parts. The movement of thecam parts is obtained in one embodiment by means of pivotal switch levers, one end of which is acted on by a cam. Altematively, in another embodiment the movement of the cam parts is obtained by other cams which are guided directly into engagement with the cam parts.

In one embodiment of the present invention, all of the cam parts, including in particular the needle sinkers together with their displacement devices, are supported under spring action in a direction vertical to the needle butts. In this connection, all of the cam parts, including those which are normally mounted fixed in position, can be raised by associated mechanical switching devices, whereupon they may or may not be individually held selectively by the locking devices corresponding to the performance intended.

By means of a fixed cam, the cam parts can be moved into their rest position, or they can be moved into their working position. Each electromagnet of the locking device may suitably be provided with a spring-actuated detent bolt.

The switchable cam arrangement of the invention is preferably constructed in the manner that the cam parts comprise plates arranged on guide bolts. In this case, the detent bolts then engage into detent grooves in the guide bolts of the cam parts. This construction has the advantage that only the guide bolts and not the more complicatedly-shaped cam or lock part itself need be directly guided.

For easier locking, the cam parts can be raised into their operating position by springs and be removed from the operating position by cams.

There has thus been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of

course, additional features of the invention that will be described hereinafter and which will form the subject of the claims appendedhereto. Those skilled in the art.

will appreciate that the conception upon which this disclosure is based may readily be utilized as abasis for the designing of other structures for carrying out the several purposes of the invention. It is important,-there-- fore, that the claims be regarded as including. such equivalent construction as do not depart from and scope of the invention. Y

A specific embodiment of the invention has been chosen for purposes of illustrationand description, andp tion; 1

FIG. 2 is a-view similar to FIG. 1 and'showing the cam lift lever in its lowered position;

' FIG. 3 is an edge view of a portion of a knitting machine needle bed having the switchable cam arrangements of the present invention (partially broken away) mounted thereabove;

FIG. 4 is a top view on an enlarged scale of the arrangements shown in FIG. 3; I

FIG. 5 is an enlarged fragmentary viewof one portion of the cam arrangement of FIG. 3; and 1 FIG. 6 is a top view of the arrangement shown in F IG'.

5. I In FIGS. 1 and 2, a knitting machine cam is actuated via a switch lever from associated lever cams. A lower needle raiser l and an upper needle raiser 2 are fasthe-spirit.

tened to long guide bolts 3 and 4. These guide bolts are pulled and prestressed by tension springs 5 and 6 at all times in the direction of the arrows A indicated in FIG. 1. In each guide bolt there is fastened a pin and 8 which bears against a switch lever 9. The lever 9 is pivotally supported on a bearing 10. The lever 9 has an arm 11 which extends away from the guide bolts 3 and 4. This arm 11 engages, at each side of the knitting machine, a cam 12 which is fixed onto the machine. The guide bolts 3 and 4 are guided at their end adjacent the needle raisers 1 and 2 in a guide plate 14, and at their end extending away from the needle raisers in a guide plate 13.

Each of the guide bolts 3 and 4 has one or more detent grooves 15 and 16 into which spring-loaded detent bolts 17 and 18, actuated by corresponding electromagnets 19 and 20, respectively, can engage. The direction of movement of the spring-loaded detent bolts 17 and 18 is perpendicular to the direction of movement of the guide bolts 3 and 4. In FIG. 1, there is shown an operating position of the device in which the electromagnet 20 has attracted and has brought the detent bolt 18 into engagement with the detent groove 16 of the guide bolt 4. The electromagnet 19, on the other hand, is not connected and the detent bolt 17 is, therefore, not in engagement with the detent groove 15 of the guide bolt 3. A lock part 21 is firmly connected with the guide plate 14.

In FIG. 2, the device is shown in an operating position with the lever arm 11 of the switch lever 9, having been moved downwardly by the cam 12 on the sides of the knitting machine. In this position, the lever arm has freed the pins 7 and 8 for downward movement. The guide bolt 3 is pulled, in FIG. 2, by its corresponding spring 5 until a limiting collar 22 abuts against the guide plate 13. The downward movement of the guide bolt 3 is thus limited by the limiting collar 22. The lower needle raiser 1 is thus moved to its operative position.

The guide bolt 4, which has a limiting collar 23 corresponding to the limiting collar 22, is held fast by the detent bolt 18 of the actuated electromagnet 20 which engages into the detent groove 16 to hold the guide bolt upwardly with its needle raiser 2 in a rest position. With this arrangement, it is possible to preselect or obtain the adjustment of the cam parts mechanically by the switch lever 9 and to hold the. cam parts themselves selectively via the electromagnets l9 and 20 and their detent bolts 17 and 18 in the raised position. The electromagnets 19 and 20 can be very small since they merely have to move the small detent bolts 17 and 18, respectively, in a direction perpendicular to the direction of movement of the guide bolts 3. and 4.

In FIGS. 3 to 6, there is shown an embodiment-of the lock of the invention in which earns 24 and 25 are fastened directly on the needle bed 26 of the knitting machine. In this way, transmission members such as the switch levers 9 of FIGS. 1 and 2 and the like, which are very difficult to arrange in the carriage of the knitting machine, are avoided. FIG. 3 shows a portion of the knitting machine, seen from the bottom of the needle bed.

FIG. 4 is a top view of the apparatus of FIG. 3, the guide plate 14 being indicated merely in dash-dot line for the purposes of easier readability of the figure, while the cam parts are shown in solid lines. The mounts for various electromagnets 19, 19a, 20, 20a, 32

and 32a have also been omitted from the drawing in order not to clutter it. A cam part 27 is supported by A spring action on two guide bolts 28 and 29 so that it can move away upon passing over the cams 24 and 25, respectively. In the embodiment shown in this drawing, only cam parts 21 and 210 are mounted in fixed position, because they are not acted on by either of the two cams 24 and 25, respectively. Needle lowerers 30, 31, 30a and 31a are supported under spring action together with their adjustment devices 33, 38, 33a and 38a, respectively, on corresponding guide bolts 34, 35, 36, 37, 34a, 35a, 36a and 37a, respectively.

FIG. 5 shows an enlarged portion of the cam device of FIG. 3 in an operating position in which the cam device has moved onto the cam 24. As can be seen in the drawing, the needle lowerers 30 and the needle raisers 1 and 2 have been forced upward by an inclined surface 39 of the cam 24.

FIG. 6 shows the various elements of the cam arrangement of FIG. 5 in top view. Depending uponthe particular knitting pattern to be carried out, various ones of the cam holding electromagnets 19, 20 and 32 are energized or deenergized by the control device of the machine so that, as the cams move across the needle bed, the successive positions of the needle cams will be determined.

What is claimed is:

1. Switchable cam lock arrangements for knitting machines in which the selection and establishing of the positions of cam parts takes place by mechanical displacement of individual cam parts and wherein the cam parts are held in these positions by electromagnets, said arrangements comprising means for moving said cam parts against a bias force to given positions, and locking devices for holding said cam parts in said given positions, said locking devices being actuated by separate electromagnets said locking devices including a detent bolt movable along a path in a direction perpendicular to the direction of movement of the cam parts into and out from a detent groove on said cam parts.

2. Switchable cam lock arrangementsaccording to claim 1, wherein the means for moving said cam parts comprises a lever arranged to engage a fixed cam on the edges of the knitting machine.

3. Switchable cam lock arrangements according to claim 1 wherein the means for moving the cam parts comprises further cam means fixed on the knitting machine to be engaged directly by the cam parts.

4. Switchable cam lock arrangements according to claim 1, wherein said cam parts are spring biased in a verticaldirection to the needle butts.

5. Switchable cam lock arrangements according to claim 1, wherein the cam parts are switchable into their rest position by means. of a fixed cam.

6. Switchable cam lock arrangements according to claim 1, wherein the cam partsare switchable into their operating position by means of a fixed cam.

7. Switchable cam lock arrangements according to claim 1, wherein each electromagnet is provided with a spring-actuated detent bolt.

8. Switchable cam lock arrangements according to claim 1, wherein the cam parts comprise plates mounted on guide bolts.

9. Switchable cam lock arrangements according to claim 8, wherein the detent bolts engage in detent grooves in the guide bolts.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 66 754 1 Dated October 23, 1973 Inventor) HANS SCHIEBER, ET AL.

I It is certified that error appears in the aboveidentified patent and that said Letters Patent are hereby corrected as shown below:

Title page, Column 1, item [731 delete "G.m.b.H

and substitute -KG--.

Signed and sealed this 2nd day ofduly 1974.

(SEAL) Attest: I

EDWARD M. FLE'gCHER, JR. c. MARSHALL DANN Attestlng Off1cer Commissioner of Patents USCOMM-DC 60376-P69 FORM PO-YOSO (1069) V t .s. covzauulur rammm omcc; I!" o-us-.n4 

1. Switchable cam lock arrangements for knitting machines in which the selection and establishing of the positions of cam parts takes place by mechanical displacement of individual cam parts and wherein the cam parts are held in these positions by electromagnets, said arrangements comprising means for moving said cam parts against a bias force to given positions, and locking devices for holding said cam parts in said given positions, said locking devices being actuated by separate electromagnets said locking devices including a detent bolt movable along a path in a direction perpendicular to the direction of movement of the cam parts into and out from a detent groove on said cam parts.
 2. Switchable cam lock arrangements according to claim 1, wherein the means for moving said cam parts comprises a lever arranged to engage a fixed cam on the edges of the knitting machine.
 3. Switchable cam lock arrangements according to claim 1, wherein the means for moving the cam parts comprises further cam means fixed on the knitting machine to be engaged directly by the cam parts.
 4. Switchable cam lock arrangements according to claim 1, wherein said cam parts are spring biased in a vertical direction to the needle butts.
 5. Switchable cam lock arrangements according to claim 1, wherein the cam parts are switchable into their rest position by means of a fixed cam.
 6. Switchable cam lock arrangements according to claim 1, wherein the cam parts are switchable into their operating position by means of a fixed cam.
 7. Switchable cam lock arrangements according to claim 1, wherein each electromagnet is provided with a spring-actuated detent bolt.
 8. Switchable cam lock arrangements according to claim 1, wherein the cam parts comprise plates mounted on guide bolts.
 9. Switchable cam lock arrangements according to claim 8, wherein the detent bolts engage in detent grooves in the guide bolts. 